FIX: DRDA Client cannot connect to DB2 for z/OS via IBM DB2 Connect gateway when configured for encrypted authentication

Applies to: Host Integration Server 2016


DRDA client supporting the DB2 connector within Excel cannot connect to DB2 for z/OS through an intermediary IBM DB2 Connect gateway when gateway is configured for encrypted authentication by using AdvancedEncryption Standard (AES) instead of Data Encryption Standard (DES), returning an authentication failure error.


DRDA Client cannot determine correct encryption algorithmat connect time. Use ADO.NET provider for DRDA (DrdaClient) or ADO.NET providerfor DB2 (MsDb2Client) connection string argument EncryptionAlgorithm=AES toinstruct DRDA Client to utilize DRDA Encryption Algorithm (ENCALG) AdvancedEncryption Standard (AES) on DRDA Security Mechanism (SECMEC) when processingDRDA Security Check (SECCHK).


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. 


This issue is fixed in the following cumulative update for Host Integration Server:


Learn about the terminology that Microsoft uses to describe software updates.

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